Hematologic and hemostatic disorders are common causes of morbidity, mortality and hospital admissions. The NHLBI supported Transfusion Medicine Hemostasis Clinical Trials Network (TMH-CTN) was developed 4 years ago to conceive, develop and perform network based clinical trials addressing important questions in transfusion medicine and hemostasis. Case Western Reserve University/University Hospitals of Cleveland has been an active member of this network, and under the direction of the applicant played an important role in the mission of the TMH-CTN. The purpose of this application is to describe the activities of the applicant and institution, and to define the direction of the TMH-CTN network over the next funding period, if awarded. The mission of the network over this period is to continue to evaluate promising new therapies for hemostatic disorders such as immune thrombocytopenic purpura (ITP) and thrombotic thrombocytopenic purpura (TTP), as well as new blood products such as platelets and platelet substitutes, thrombopoetin analogues and cytokines. Other disorders including hemophilia, heparin-induced thrombocytopenia, and autoimmune hemolytic anemia will also provide substrates for further investigation. Through regular participation in disease-oriented subgroups, the TMH-CTN steering committee, training of institutional participants in disorders relevant to the network, and oversight of ongoing clinical trials, the applicant hopes to continue to make contributions to the TMH-CTN through by devoting personal energy and insight as well as harnessing the clinical resources of Case Western Reserve University, University Hospitals of Cleveland and Rainbow Babies and Children's Hospital to successfully perform network based trials focused on important disorders relevant to the areas of hemostasis and transfusion medicine over the next years.